Combine 1 cup sugar, baking powder, flour and salt in a mixing bowl.
Add yolks, lemon zest and ¾ tbsp. lemon juice.
Cut in butter with a pastry blender until coarse crumbs form.
Press half of the mixture into the bottom of a greased 9x13” baking dish.
Place peaches, remaining half cup sugar, cornstarch, cinnamon, and ¾ tbsp. lemon juice in a small bowl.
Stir to combine.
Allow peaches to sit for 5 minutes.
Layer peaches over top of crust layer.
Sprinkle remaining crust mixture over top of peaches.
Bake at 350° for 50-60 minutes or until golden.
Cool completely.
Cut into bars.